Construction of Pd/Ni2P-Ni foam nanosheet array electrode by in-situ phosphatization-electrodeposition strategy for synergistic electrocatalytic hydrodechlorination

Designing a high-efficiency electrocatalyst with low Pd loading on the electrodes is the key to the electrocatalytic hydrodechlorination (EHDC) of chlorophenols (CPs) but still challenging. Herein, a novel three-dimensional network structure Pd/Ni2P-Ni foam nanosheet array electrode with Pd loading content only 1 wt% was prepared by an in-situ phosphatization-electrodeposition strategy for robust EHDC. The EHDC performance of the constructed Pd/Ni2P-Ni foam electrode was tested with 4-CP as the model pollutant. Complete dechlorination is achieved within 90 min, and the consumption of Pd is reduced by 50 %. The mechanism study shows that the improvement of EHDC performance can be attributed to the synergistic effect of Ni2P nanosheets and Pd NPs, in which Ni2P replaces Pd-0 to produce atomic hydrogen (H-ads), and promotes more Pd2+ generation, which is beneficial to the fracture of the C-Cl bond, thus improving the mass activity of Pd and the EHDC performance simultaneously. This work provides a simple and practical strategy for designing low noble metal supported catalysts with high EHDC performance.